package top.fsfsfs.config;

import org.springframework.aop.interceptor.AsyncUncaughtExceptionHandler;
import org.springframework.aop.interceptor.SimpleAsyncUncaughtExceptionHandler;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.AsyncConfigurer;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

import java.util.concurrent.Executor;
import java.util.concurrent.ThreadPoolExecutor;

@Configuration //表明该类是一个配置类
@EnableScheduling
@EnableAsync(proxyTargetClass = true) //开启异步事件的支持
public class ThreadPoolAsyncConfig implements AsyncConfigurer {

    @Bean(name = "mainThreadPoolAsyncExecutor")
    public Executor MainThreadPoolAsyncExecutor() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        //核心线程数10
        executor.setCorePoolSize(10);//线程池创建时候初始化的线程数
        //最大线程数20
        executor.setMaxPoolSize(20);//线程池最大的线程数，只有在缓冲队列满了之后才会申请超过核心线程数的线程
        //缓冲队列200
        executor.setQueueCapacity(200);//用来缓冲执行任务的队列
        //允许线程的空闲时间60秒
        executor.setKeepAliveSeconds(60);//当超过了核心线程出之外的线程在空闲时间到达之后会被销毁
        //线程池名的前缀
        executor.setThreadNamePrefix("MAIN-LOGS-ASYN-");//设置好了之后可以方便我们定位处理任务所在的线程池

        executor.setWaitForTasksToCompleteOnShutdown(true);//用来设置线程池关闭的时候等待所有任务都完成再继续销毁其他的Bean
        executor.setAwaitTerminationSeconds(60);//该方法用来设置线程池中任务的等待时间，如果超过这个时候还没有销毁就强制销毁，以确保应用最后能够被关闭，而不是阻塞住

        //线程池对拒绝任务的处理策略
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());//这里采用了CallerRunsPolicy策略，当线程池没有处理能力的时候，该策略会直接在 execute 方法的调用线程中运行被拒绝的任务；如果执行程序已关闭，则会丢弃该任务
        executor.initialize();// 初始化

        return executor;
    }

    @Override
    public Executor getAsyncExecutor() {
        return MainThreadPoolAsyncExecutor();
    }

    @Override
    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
        return new SimpleAsyncUncaughtExceptionHandler();
    }
}
